This application claims the benefit of Japanese Patent Application Number 2003-68604 filed on Mar. 13, 2003, the entirety of which is incorporated by reference.
1. Field of the Invention
This invention relates to a pressure fryer which includes an oil vat for containing cooking oil, a heating means for heating the oil vat, and a lid which is able to hermetically seal the oil vat so as to cook foods such as fried chicken or fried potatoes with heat and pressure.
2. Description of the Related Art
A conventional pressure fryer includes an oil vat for containing cooking oil, a heating means for heating the cooking oil, such as a burner, a lid which is capable of sealing an opening of the oil vat when the oil vat is heated, a pressure releasing means for releasing the pressure in the oil vat, such as an open/close valve, and a controlling means for controlling the heating means and the pressure releasing means. With this structure, cooking oil in the oil vat is heated by operating the heating means according to a predetermined cooking menu in which a cooking temperature and a cooking timer is set. Whereby, foods put into the oil vat can be cooked with heat and pressure.
Moreover, when the cooking timer finishes, the controlling means stops the operation of the heating means while releasing the pressure in the oil vat using the pressure releasing means, so that the oil vat can be opened.
However, after the cooking timer finishes and the pressure starts to be released, it takes time to release the pressure in the oil vat completely. Due to this, steam or oil smoke could gush out by extra remaining pressure when a user opens the lid at the time of notification of time up. A cooking apparatus to solve the problem is disclosed, for example, in Japanese patent publication of unexamined application No. 1-274721. It includes first register means for storing timing information relating to a cooking process following a cooking control program and means for decrementing the first register means as the cooking process continues. It also includes second register means for storing timing information relating to a pressure control means such as an open/close valve, and means for decrementing the second register means as the cooking process continues for causing the second register means to reach zero slightly before the first register means reaches zero, and thus pressure in the cooking apparatus is released slightly before the cooking cycle is completed.
However, since pressure in the oil vat varies according to a kind and an amount of foods, there is a gap in a timing between time up and complete release of pressure in the oil vat if a cooking termination is monitored based on time. Therefore, a lid could be opened when there is extra remaining pressure in the oil vat.
In order to solve the above problem, an object of the present invention is to provide a pressure fryer capable of judging a termination of cooking in a safe state without fail regardless of a kind and an amount of foods.
A pressure fryer of a first aspect of the present invention includes a pressure detecting means for detecting the pressure in the oil vat and a controlling means for judging the termination of cooking when lowered pressure in the oil vat is detected by the pressure detecting means after the cooking timer finishes.
According to a second aspect of the present invention, in addition to the object of the first aspect, a pressure fryer has a configuration in which the pressure detecting means is a pressure switch which is turned ON at set pressure, and the controlling means is a means for detecting the lowered pressure by receiving an OFF signal of the pressure switch in order to confirm the lowered pressure easily without fail.
According to a third aspect of the present invention, in addition to the object of the second aspect, a pressure fryer has a configuration in which the pressure detecting means includes another pressure switch which is turned ON when pressure becomes higher than the set pressure, and the controlling means starts the cooking timer when it receives the ON signal of the pressure switch in order to start cooking in the best timing.
According to a fourth aspect of the present invention, in addition to the object of the first aspect, a pressure fryer has a configuration in which the pressure detecting means is a pressure sensor which detects pressure changes and the controlling means detects the lowered pressure by receiving a detected signal of the pressure sensor in order to confirm the lowered pressure more easily.